A problem occurred configuring root project 'android' Flutter

Whether the first time or not. When you click run on your application you get an X gradle build error If you have any of the following lines in your error even a single line then try this solution

Launching lib\main.dart on sdk gphone x86 in debug mode...

FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring root project 'android'.
> Could not resolve all artifacts for configuration ':classpath'.
   > Could not download builder.jar (com.android.tools.build:builder:3.5.0)
      > Could not get resource 'https://dl.google.com/dl/android/maven2/com/android/tools/build/builder/3.5.0/builder-3.5.0.jar'.
         > Premature end of Content-Length delimited message body (expected: 8174407; received: 4456416
   > Could not download bundletool.jar (com.android.tools.build:bundletool:0.9.0)
      > Could not get resource 'https://dl.google.com/dl/android/maven2/com/android/tools/build/bundletool/0.9.0/bundletool-0.9.0.jar'.
         > Premature end of Content-Length delimited message body (expected: 5248142; received: 4456416

SOLUTION

Go this location:- .flutter/packages/flutter_tools/gradle/flutter.gradle **

1. Backup the file in another place before making edits to it
2. Search for something called buildscript;
3. It should come up like that (or similar, don't worry you have a backup file)

and overwrite this code

 buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.2'
    }
}

With this

 buildscript {
    repositories {
        maven {
            url 'https://dl.google.com/dl/android/maven2'
        }
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.2'
    }
}

Still, your problem is not solved? If it was solved DON'T try the next one if not then try it. (And even if this didn't work then put the backup file in its place and see if it's working)

Then in your android folder go to build.gradle (in your project files go to android/build.gradle) and change the buildscript to this (Don't worry about the code not being 100% like this. Just add the specified line in the shown location and that's it)

buildscript {
    repositories {
        google()
        mavenCentral()  //add this line
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.2.1' // Doesn't matter what you have here
    }
}

Just make Flutter clean in android studio or VScode

If you already have mavenCentral() added inside buildscripts{...} and allprojects{...} inside build.gradle file,

then add jcenter() after each mavenCentral().

or, vice-versa

If you got AndroidX incompatibilities in a plugin as well then just focus on following versions:

1. change your compileSdkVersion 30 in app\build.gradel

2. Try to change this accordingly

   dependencies { classpath 'com.android.tools.build:gradle:4.1.0'

   }

3. Try to change gradle version in gradle->wrapper->gradle-wrapper.properties

distributionUrl=https://services.gradle.org/distributions/gradle-6.6.1-all.zip

I solved the problem with <uses-permission android:name="android.permission.INTERNET" /> in androidManifest.xml